: My water heater has a cheap little plastic drain valve that now leaks. To replace it I need to drain the water heater. Should I open a faucet when I drain the tank, or does a vacuum break keep the tank from collapsing when draining the entire tank? Curt

Curt,When draining a WH, you will need to open somthing at the top, a faucet open, or loosening a fitting at the top. Otherwise, you have a "thumb over the top of a straw" effect happening. I don't think you steel tank will collapse while draining the tank. If it does let me know so I can get it into the Guniess World records. Have fun with it, and if the plastic fitting breaks off while removing it, you can apply heat with a torch to melt it a bit. I have loosened them this way before. Try to take it out intact first though. Terry